Missiles are accomodated in launchers at the wings of airplanes. From these launchers they are fired by igniting the engine. Before firing the missile is connected with the airplane by one or more umbilicals. These umbilicals are released during or before the firing. The supply of the missile with electricity and cooling gas takes place via such umbilicals prior to the firing, so that the supply of electricity and cooling gas by aggregates belonging to the missile has only to take place during the flight after firing. The cooling gas is directed to a Joule-Thomson-cooler to cool a detector in the seeker head of a target-tracking missile. There is also an exchange of data available in digital form between the airplane and the missile. This exchange of data is performed through a plug. This plug is unplugged from the missile by a pull-back-mechanism shortly before the firing and pulled back into the launcher. The connections have to be made manually during the loading of the launcher with the missile. This is a source of errors. Furthermore the pulling back of the plug by a mechanical pull-back-mechanism requires time. Therefore a delay between the firing command and the actual firing has to be provided.